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Patented May 30, 1933 iii-ran STATES PATENT oFFIc NIoHoLAs BENNETT, or A PPLETON, HER-BERT noon, on GLAZEBROOK, MAnoIrE-srnnj wILI-raia COLIN srannr, or CRESSINGTON, Ann reign HOLT; or wnYB'aInGE, ENGLAND, assrcirons 'ro IMPERIAL cnnrarcar. rlvnusri ns LIMITED, a: oonrona TION GREAT BRITAIN LIANUFACTURE F CHLORIDE No Drawng. Application filed May 31, 1930, Serial No. 458,914, and in Great Britain June 1, 1929.;

This invention relates to the production of benzyl chloride. More particularly this invention relates to the recovery of benzyl chloride from solutions resulting from the benzyration of cellulose.

In another application of even date Ser. No. 458,913 we describe the production of benzyl chloride from a mixture of benzyl alcohol and other products (e. g. the mixture resulting from the benzylation of cellulose) by treatment with hydrochloric acid.

We have now found that such mixtures contain condensation products of benzyl chloride or benzyl alcohol of undefined constitution and therefore the yield of benzyl chloride does not. correspond with the total quantity of benzyl compounds present. We have further found, however, that it is possible to split up these compounds by treatment with chlorine, to produce benzyl chloride and benzaldehyde and some ben- Zoyl chloride and nuclear chlorinated derivatives. According to our invention therefore we use chlorine and in this way a considcrable quantity of benzyl chloride can be recovered from the mixture tov be treated, which would otherwise be lost.

The action of chlorine on the mixture evolves hydrochloric acid at the same time as it splits the condensation products into benzyl chloride and benzaldehyde so that benzyl chloride is simultaneously formed by the reaction of benzyl' alcohol and hydrochloric acid as described in our co-pending application. a

We prefer however to treat the crude mixture as described in our co-pending specification with hydrochloric acid and recover as much b-enzyl chloride as possible by this means. Then we take the residue obtained after distilling off the benzyl chloride and treat this with chlorine.

In this way the residue is converted to a mixture consisting substantially of benzyl chloride and b-enzaldehyde.

having obtained a product, by either of the two methods described above, COIlSlSt iiig of benzyl chloride and benzaldehyde these can be separated by any known method such as fractional distillation, or by extracting the benzaldehyde with sodium bisulfite solution and fractionating the benzylchloride remaining from the accompanying ben Zoyl chloride nuclear chlorinated derivatives. By this means-we have-obtained .yields of benzyl chloride from the originalmixture which are increased by about and in.

additionvaluable by-products. are obtained 1 such as benzaldehyde and benzoyl chloride. The benzoyl chloride can also be avoided by adjusting the amount of chlorine so that it does not exceed that required to split the condensation product into benzaldehyde and benzyl chloride without further chlorination.

Example I separated from the crude benzyl chloride layer. The crude benzyl chloride is then filtered through soda ash and distilled; 120

parts of benzyl chloride is recoveredflll specific gravity containing 90% pure benzyl chloride; I f

The still residues (sp. g. 1.06) from the j above process are treated wit-hchlorine at ordinary temperature in the ratio of about 160 parts of residues to 40 parts of chlorine.

After chlorination the residues ;(sp.-

1.095) are distilled and 124: parts of product (sp.-g. 1.085) are obtained. These products. contain approximately-1.50% pure benzyl chloride. The benzaldehyde which forms the maj or part of the residue isrecovered by extraction with sodium bisulfite and the residual oil is re-distilled for benzyl chloride.

The 'benzyl cellulose liquor referred to in the above example is obtainable when alkaliflcellulose isitreated in the, presence of wateriwith .benzyl chloride. Some of the latter.- reactsto form benzyl cellulose, some is hydrolyzed to formbenzyl alcohol, and some reacts with this latter to forin'benzyl ether. The mixture is then a mixture of dium bisulfite, and distilling the residual benzyl alcohol, benzyl chloride, benzyl ether, oil for benzyl chloride.

benzyl cellulose, sodium chloride, sodium In testimony whereof we aflix our signahydroxide and water. This is extracted, tures.

5 with a! solvent which is a.- non-solvent fon NICHOLAS; BENNETTI.

benzyl'cellulose and the sodium sal ts e. g HERBERT DODD. ethyl alcohol, and the benzyl compounds are WILLIAM COLIN SPRENT. thus removed; The alcohol is distilled off F RED- HOLT.

and; the crude benzylation mixture results. It contains perhaps 1030% of benzyl ether, -80% of benzyl alcohol, 510% of benzyl chloride, less than 5% of condensationproduct, less than 5% water, and perhaps some iron. 15 An advantage of this invention is the re- 80 covery of more nearly quantative. amounts oi; benzyl; chloride than. was heretofore possi le.

As. many' apparently widely different embodiments. of v this invention. may be made without departing from the spirit and; scope thereof, it; is to be understoodthat wedo not: limit; ourselves.- to. the specific embodiments thereof; except as. defined in the. appended claims. 90

We claim 1'. Themethod& of reducing. condensed." benzyl compounds, resulting from the ben-. zylation ofi cellulose, comprising. treating them with chlorine.

2. In the recovery ofbenzyl chloride from solutionsicontaining benzyl alcohol. from the benzylationof. cellulose the step which con1-. prises .treatingthe solution with chlorine. I

3. The preparation. of: benzyl: chloride. 100

from liquors resulting "from 1 the benzylation of cellulose and containing benzyl: com-H pounds in solution comprisingtreating. with. an anhydrous inorganic alkaline substance,

separatingthe liquorsfromtlie alkaline sub-. 105

stance thereafter treating; with hydroohlo-. ric acid, removing thehenzyl' chloride and. thereafter treating. the residualrliquor with chlorine. 4; Themethod of preparingrbenzyl'ichloa. 110

ride comprising treating a liquor-{resulting from the lbenzylationof cellulose and containing benzyl compounds with sodium carbonate, separating the liquor from theiso I "-dium carbonate thereafter. treating=Withhy-. 115

drochloric acid and removing. the 'benzy'li chloride, treating the residual. liquor with.

chlorine in suchamount as to inhiliitJthe formation of benzoyl: chloride. andi removingthe benzyl chloride. 120

5. The method of preparing henzylfichloa.

ride comprising treating liquor resulting;

from the henzylati on of cellulose. and; cone taining benzyllcompouncls.among which is benzyl alcohol, with sodium: carbonate, there-..

after treating the liquor.- with hydrochloric:

the liquor, and treating the. liquor with-ch10.

rineinthe ratio ofaboutlGO partsofliquon to 401parts.of chlorine, extracting with so. 

